The present invention relates to an improvement in a tarpaulin covering system and more particularly, relates to a tarpaulin rod securing device.
The use of tarpaulins for covering an open box-like container such as a truck box or a storage bin is well known in the art. Thus, as shown in U.S. Pat. No. 4,484,777, there is provided a truck box having parallel side walls joined by transverse front and back end walls, with a flexible fabric cover fixed at one lateral edge to one side wall, and attached at the opposite lateral edge to a roll tube or rod which is rotatable from side to side along the top surfaces of the front and back end walls of the truck box to permit winding and unwinding of the fabric from the rod or tube to thereby permit covering and uncovering of the box structure. The tarpaulin rod is operated manually by a handle structure connected to the roll tube by a universal joint.
There is also known in the art to use automated means for winding and unwinding the rod and associated tarpaulin. Thus, there is shown in U.S. Pat. No. 4,673,208 a hydraulic system for moving a tarpaulin from one side to the other. It is also known from various patents to utilize an electric motor for the same purpose.
The tarpaulins are used to cover either the open top of a container or alternatively, may be utilized to cover a side wall.
Typically, when used to cover an open top container, the tarpaulin is there to prevent any portion of the load being blown from the open top of the container which can not only cause unnecessary wastage of the transported goods, but can also create dangerous situations. Thus, the danger of loose material being blown out of the container can cause pollution of the surrounding area and also create potentially dangerous situations for vehicles following the container. Accordingly, certain jurisdictions have imposed regulations requiring the use of tarpaulins.
Various configurations of tarpaulins have been proposed. However, two configurations have proven to be particularly popular. One such configuration is the so called end-rolled tarpaulin which is gathered at one of the longitudinal ends of the container when not in use and moved along the body of the container between operative and stored positions. The end-rolled tarpaulins are typically gathered at the front end of the vehicle and are usually provided along their length with a number of transverse supporting bars which extend between the two longer side walls of the container. The end-rolled tarpaulins are typically moved by means of a pair of cables trained over pulleys and carrying the tarpaulins with them as they move.
The other type of permanently installed tarpaulin preferred by some hauliers is referred to as the side-rolled tarpaulin. These so called side-rolled tarpaulins which permanently extends the full length of the container body are rolled and unrolled about a roll rod that also extends the full length of the container body.
The use of prior art flexible closures such as prior art tarpaulins to close or cover the loading aperture of open top containers is associated with a number of drawbacks. One major shortcoming related to prior art assembles involves the difficulty often encountered in drawing the flexible closures into a proper extended or closed configuration. Indeed, the relatively heavy, bulky and flexible nature of large tarpaulins often cause such closures to be quite difficult to draw into properly extended or closed position for service as cover.
Another main drawback associated with prior art assemblies relates to the difficulty in keeping the tarpaulin taut during the rolling and unrolling operations which leads to potential damage to the involved structures. This situation also leads to difficulties in establishing a suitable weather resistant seals about the perimeters of properly extended closures. The difficulty in keeping proper tension on the tarpaulin during rolling and unrolling operations is compounded in certain situations as for example when there exists a relatively moderate or high wind causing the tarpaulin to catch in the wind. In such instances, it is sometimes necessary to face the truck trailer in such a manner that the wind will not catch the tarpaulin. This may prove to be impossible when the wind changes direction. The difficulty in maintaining the tarpaulin in a taut state during rolling and unrolling operations leads to possible ripping or tearing of the tarpaulin and associated structures.
The difficulty in maintaining the tarpaulin in a taut state during rolling and unrolling operations also potentially leads to an improper seal which, in turn, may lead to potentially dangerous road condition and loss of material. This problem has been addressed by some of the prior art structures. However, most prior art structures or assemblies lack an effective means of maintaining the cover taut and in place during transportation especially at highway speeds. Indeed, the investment of time and effort that typically must be extended to properly secure a prior art tarpaulin to prevent its being drawn out of proper position by environmental conditions often proves to be unwieldy. Some prior art assemblies make use of a series of straps spaced along the tarpaulin which are secured to the container side wall by tying or clamping. These prior art assemblies have proven to be unsatisfactory since they have demonstrated a tendency to admit dust or rain under the tarpaulin and to allow the bulk material to flow between the peripheral edges of the tarpaulin and of the container. Also, at highway speeds, the tarpaulin is subject to billowing.
It is therefore an object of the present invention to provide a means for maintaining or securing the tarpaulin rod or tube in place after the tarpaulin has been unwound therefrom.
According to one embodiment of the present invention, there is provided, in a vehicle having an open area covered by a tarpaulin, and wherein the tarpaulin is moved from an uncovering position to a covering position by means of a longitudinal rotating tarpaulin rod, the improvement comprising a tarpaulin rod securing device, the tarpaulin rod securing device comprising a first member having a recess formed therein, an access opening to the recess, the recess being sized to receive the tarpaulin rod, and a second movable member, the second movable member being movable between a first position wherein the tarpaulin rod may have access to the recess, and a second position wherein the movable member secures the tarpaulin rod within the recess.
According to a further embodiment of the present invention, there is provided a tarpaulin rod securing device comprising a first member having a recess formed therein, an access opening to the recess, and a second movable member pivotably connected to the first member and being spaced therefrom to provide a gap therebetween, the second movable member being movable between a first position wherein the second movable member permits access to the recess, a second position wherein the movable member prevents access from the recess.
The tarpaulin rod securing device of the present invention may be utilized in several different configurations including one wherein the tarpaulin extends over an open top container and also in the so-called side-rolled tarpaulins.
As aforementioned, there is provided a first member which has a recess and an access opening to the recess. The recess is preferably of a U-shaped configuration although it is within the scope of the invention to use different configurations.
The movable member is mounted such that it may be moved between first and second positions. Preferably, the second member is pivotably connected and is provided with an angled bottom surface such that in a normal position, it will prevent a member from exiting the recess while permitting entry thereto.